Trending, then peaking, then past its sell-by date

Australian scientists have discovered that the more beards there are, the less attractive they become. Their experiment, reported in the journal Biology Letters, found that “women and men judged heavy stubble and full beards more attractive when presented in treatments where beards were rare than when they were common … Likewise, clean-shaven faces were least attractive when clean-shaven faces were most common”. Put simply, when only a few men have beards, they are seen as more attractive, but when beards become the norm it is the clean-shaven man who has a competitive advantage. The technical term for this is “negative frequency-dependent sexual selection”, but most of the media coverage highlighted the researchers’ use of the term peak beard (a recent addition to our Open Dictionary).

“Peak beard” is a playful adaptation of the better-known term peak oil. This refers to the idea that, at some point, the amount of oil being extracted from the earth will reach a peak, and after that it will decline rapidly because oil is a finite resource. (There is a lot of disagreement about timing: some say peak oil has already happened, others say it is still some way off.) The noun peak literally means a mountain, or the pointed top of a mountain, but this meaning is now far less common than the figurative one (“the point when something reaches its highest level”). The noun peak has been around for hundreds of years, but its use as a verb is more recent, and here the meaning usually includes the idea that, having reached a peak, something then goes into decline:

Zinc inventories have been steadily heading south since peaking at 1.24 million tonnes in October 1994.
Car pooling decreased, continuing a long slide that started after it peaked during the oil crisis of the 1970s.
There are signs that cigarette smuggling may have peaked.

On the model of “peak oil”, a number of other resources have been described in these terms, such as gold, coal, and gas. And the term peak water – the scary idea that humans have already used up all the easily available water – was named as one of the New York Times words of the year in 2010. An interesting variation is peak car, the hypothesis that – in many western countries, at least – the number of cars has already reached its highest point and is now declining. This looks plausible: as traffic congestion worsens, it gets to a point where people start to look at alternative ways of getting around.

As if to prove that language isn’t always logical, peak beard doesn’t quite fit this model, because (unlike oil or gas, for example) beards are a “renewable resource”. But it still conveys the idea of something becoming widespread before starting on its inevitable decline. The metaphor is fairly clear, and the process of increasing, peaking, and then declining can be represented visually as a bell curve. In the UK (and probably many other countries), beards have spread like a virus among the younger male population in recent years. Has the beard trend peaked? Well, maybe this Australian research will hasten its end.